The present invention relates to systems and apparatus for dispensing a continuous strip of strapping material from a coil thereof for use by associated strap-utilizing equipment. More particularly, the invention relates to a system for dispensing steel strapping material wound in very large, heavy coils.
Steel strapping material is shipped from the manufacturer in tightly wound coils. The strapping material is typically used with a strapping machine for wrapping the strapping around objects to be strapped. For this purpose, the coil is rotatably mounted on a suitable dispenser or coil unreeler for facilitating withdrawing of the strapping material from the coil. Such coil unreelers are disclosed, for example, in U.S. Pat. No. 3,717,313, issued Feb. 20, 1973 to W. Q. Williams, U.S. Pat. No. 3,688,999, issued Sept. 5, 1972 to R. F. Plattner et al., and U.S. Pat. No. 3,162,394, issued Dec. 22, 1964 to J. W. Culpepper et al. In each of these prior art unreelers, the coil is mounted on a hub structure for rotation by suitable drive means or by withdrawing force exerted on the withdrawn portion of the strapping material by the strapping machine or other strap-utilizing apparatus.
These dispensers and coil unreelers are quite suitable for use with coils weighing up to a few hundred pounds. But in recent years steel strapping material is being provided by the manufacturers wound in much larger coils, weighing up to one thousand pounds and more, and it may be expected that still larger coils will be forthcoming in the future. The handling of these extremely heavy coils is quite difficult and in some cases virtually impossible, since it has been found that even forklift trucks have great difficulty in handling one-thousand-pound coils. Thus, the prior art coil dispensers and unreelers are unsuitable for use with today's heavier coils because all of these prior dispensers require considerable handling of the coil in order to place it on the unreeler, particularly with vertical-type unreelers of the aforementioned U.S. Pat. Nos. 3,717,313 and 3,688,999.